Updated

Two media rights groups condemned the Egyptian army for assaulting and arresting journalists who were covering a recent violent crackdown on antimilitary protests in Cairo.

The Paris-based Reporters Without Borders said Tuesday it recorded 32 attacks on journalists during clashes last Friday in the Egyptian. It said at least 20 reporters were assaulted or beaten and 11 injured. The New-York based Committee to Protect Journalists, meanwhile, urged Egypt's ruling military council to investigate allegations that two journalists were "viciously beaten up by soldiers."

More than 300 people, including reporters, were detained during Friday's violence, which broke out when thousands of protesters marched toward the Defense Ministry demanding the country's military rulers step down immediately. It was the largest security roundup following protests.

At least nine of the journalists who were arrested have been released, pending investigation by military prosecutors into allegations of attacking troops and disturbing public order. More than a dozen female protesters, and a similar number of students, have also been released pending investigation. They could all face military trials.

A military official said those who have been released will be called in for further questioning, explaining that the journalists had insufficient documents because they were not members of the press syndicate. He was speaking on condition of anonymity in line with military regulations.

The military took over from longtime Egyptian leader Hosni Mubarak, who was ousted in a popular uprising in February 2011. But its rule has been marred by periodic violence and angry protests over its management of the transition and continuation of many of Mubarak's repressive practices.

Journalists have often been the target of beating and harassment while covering the protests. Reporters Without Borders said in a report released earlier this month that the military is still using "the same old methods of censorship and intimidation" as the ousted regime.

In the May 4 protests, Belgian photojournalist Virginie Nguyen, who works for the local English online daily Egypt Independent, was injured during the protest when a rock hit her face. At the hospital for treatment, an army officer shouted at her and asked her to hand over her camera.

She told the newspaper in a video recording that she handed over her camera, but the officers still "decided to arrest me and the woman with me."

She said she was taken to an army hospital, where she was roughed up, and then to another hospital where she refused to have surgery. She was later transferred to a security office for questioning, and then let go.

"They erased all the pictures of the soldiers," she said. "I was lucky they didn't take my camera... It is not this that will make me stop taking pictures."

The Committee to Protect Journalists said that two other journalists, Ahmed Ramadan and Islam Abu al-Ezz, were both brutalized while in military custody, and demanded an investigation into the allegations.

The two journalists, who work for the privately-owned el-Badil online daily, said they were first attacked by thugs, then handed to the military police who allegedly beat them up in custody, according to el-Badil. The publication posted pictures of the two journalists, their bodies covered in bruises. It said they were released after two days.

"These reports depict an anything-goes atmosphere in which military authorities act with impunity," said CPJ spokesman Mohamed Abdel Dayem. "The council must send a clear message that it will not tolerate such a climate."

According to Reporters Without Borders, several TV crews were attacked by the military police, who smashed their mobile phones, confiscated cameras and deleted footage and photographs. Among those attacked was Qatari-based Al-Jazeera Live Egypt crew and local Egyptian stations such as ONTV, el-Tahrir and CBC.

Activists have also increasingly been targeted by authorities.

Blogger Asmaa Mahfouz, a leading figure in last year's uprising, was sentenced in absentia Tuesday to a year in prison and fined $330 for assaulting a pro-military supporter earlier this year. Her lawyers say the charges were politically motivated and they will appeal.

Although Mahfouz's case predates the violent protests last week, lawyers say there is an escalation against antimilitary activists ahead of presidential elections scheduled to begin on May 23.

"There is an attempt to terrorize activists and political groups in a bid to bury any protest," lawyer Ahmed Ragheb said. Some protesting outside the military prosecution to demand the release of the protesters were also detained.